Fittings for attaching seats securely to aircraft are many and varied. Optimal use of available space coupled with secure and safe connections while maintaining ease of assembly and disassembly are the goals sought in the design of aircraft seat anchors.
Many types of fittings have been designed to removably secure an aircraft seat within tracks upon which the seat is carried, which tracks are mounted such as by bolting them to the floor of the aircraft. These fittings are secured to the seat legs and the fittings are received in the tracks and secured at select locations of the tracks to provide adjustable spacing for legroom for a particular seat, for example the pilot, or to provide adjustment of the spacing between rows of seats.
U.S. Pat. No. 5,083,726, and the references cited therein, disclose various fittings used to removably secure an airplane seat within a track mounted to the floor of the airplane. In such devices, factors which must be considered include the very high loads which must be sustained, on the one hand, as well as the elimination of noise or rattle caused by the plane's vibration.
The '726 patent discloses one type of known fitting wherein the bearing section of the fitting comprises an opening defined by two truncated conical walls with the abutting truncated sections providing a bearing site. The open ends of the opening are surrounded by segmented spherical bearing surfaces which carry caps having conforming internal, spherical bearing surfaces. A pin passes through the assembly of caps and bearing section to secure the leg in position. A plastic, box-like anti-rattle device to prevent rattling is mounted to the rear of the track fitting and bears against the top of a track receiving the fitting.
Still further, U.S. Pat. No. 5,520,357 discloses a fitting for attaching a galley wall or bulkhead to the interior of the aircraft. The fitting employs a separable attachment plate and a bolt. The bolt serves to link the galley to the floor through the attachment plate, a track affixed to the floor, and a threaded anchor nut located within the track. The bolt is inserted through the attachment plate into the anchor nut from above after the bulkhead has been set in place on the track and attachment plate, avoiding the need to raise the bulkhead when connecting it to the fitting.
Prior fittings have achieved success to varying degrees in meeting the stated goals of an optimal seat anchor. The aircraft seat track anchor fitting according to the present invention provides defined improvements over prior fittings and is especially suited for a particular aircraft, although its principles are adaptable to many other types of aircraft.